A researcher is culturing several different strains of bacteria in the same petri dish. One day, he finds that all of the strains have died off except one. He continues to grow his bacteria for several weeks, and new strains develop
However, after a month he again notices that all but
one of his bacterial strains have died off. This is an example of:
A. acyclic selection.
B. continuous selection.
C. artificial selection.
D. nonperiodic selection.
E. periodic selection.
E
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Plants have developed both cuticles and crassulacean acid metabolism (CAM) in an attempt to limit which of the following?
A. photorespiration B. excess photosynthesis C. PEP carboxylase loss D. water loss
Which of the following statements is not true of the value ?H?
A) ?H is the change in heat content. B) ?H is the change in enthalpy. C) In biology, ?H is basically the same as ?E. D) A reaction with a positive ?H value is exothermic. E) ?H = ?E + ?(PV)
In the presence of carbon dioxide
A. hemoglobin dissociates. B. hemoglobin is not able to bind with bicarbonate. C. hemoglobin changes shape, causing it to give up oxygen more readily. D. the formation of bicarbonate causes oxygen to bind more tightly to hemoglobin.
Serologic tests may be used to detect ________ for diagnosis of disease.
A. the concentration of serum proteins B. the ability of the patient's antibodies to activate the complement system C. antigen-specific antibodies D. specific epitopes E. the proportion of plasma in a patient's blood